4Fambro D B, Fitzpatrick K, Koppa R. Determination of Stopping Sight Distances,NCHRP Report 400[R]. Wash ington D. C.. National Research Council, 1997.
6Fambro D B, Fitzpatrick K, Koppa R. Determination of stopping sight distances, NCHRP report 400 [ R ]. Washington DC: National Research Council, 1997.